feat(db)!: drop song_groups, introduce label_id on song_slides, add song_arrangement_labels (BREAKING)

database/migrations/2026_05_03_100600_refactor_songs_to_labels.php

@@ -0,0 +1,38 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class () extends Migration {
+    public function up(): void
+    {
+        Schema::table('song_slides', function (Blueprint $table) {
+            $table->dropUnique(['song_group_id', 'order']);
+            $table->dropIndex(['song_group_id']);
+            $table->dropForeign(['song_group_id']);
+            $table->dropColumn('song_group_id');
+        });
+
+        Schema::table('song_slides', function (Blueprint $table) {
+            $table->foreignId('label_id')->nullable()->constrained('labels')->restrictOnDelete();
+        });
+
+        Schema::dropIfExists('song_arrangement_groups');
+        Schema::dropIfExists('song_groups');
+
+        Schema::create('song_arrangement_labels', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('song_arrangement_id')->constrained()->cascadeOnDelete();
+            $table->foreignId('label_id')->constrained('labels')->restrictOnDelete();
+            $table->unsignedInteger('order');
+            $table->timestamps();
+            $table->index(['song_arrangement_id', 'order']);
+        });
+    }
+
+    public function down(): void
+    {
+        throw new \RuntimeException('Destructive migration: rollback not supported. Restore from backup.');
+    }
+};

tests/Feature/Migrations/SongsToLabelsRefactorTest.php

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+<?php
+
+use Illuminate\Support\Facades\Schema;
+
+test('song_slides has label_id column after migration', function () {
+    expect(Schema::hasColumn('song_slides', 'label_id'))->toBeTrue();
+    expect(Schema::hasColumn('song_slides', 'song_group_id'))->toBeFalse();
+});
+
+test('song_arrangement_groups table is dropped', function () {
+    expect(Schema::hasTable('song_arrangement_groups'))->toBeFalse();
+});
+
+test('song_arrangement_labels table exists with expected columns', function () {
+    expect(Schema::hasTable('song_arrangement_labels'))->toBeTrue();
+    expect(Schema::hasColumns('song_arrangement_labels', ['id', 'song_arrangement_id', 'label_id', 'order', 'created_at', 'updated_at']))->toBeTrue();
+});
+
+test('song_groups table is dropped', function () {
+    expect(Schema::hasTable('song_groups'))->toBeFalse();
+});